Technical Field
Embodiments of the present disclosure relate generally to wireless devices, and more specifically to techniques for correction of clock errors in wireless devices to enable reduction of power consumption.
Related Art
A wireless network generally includes two or more wireless devices (wireless stations) that communicate with each other over a wireless medium. A wireless local area network (WLAN) designed to operate according to IEEE 802.11 standard(s) is an example of a wireless network. One or both of a pair of wireless stations that communicate with each other may be designed to be operable in a low-power (or sleep) mode either periodically or sporadically. As an example, in an infrastructure basic service set (BSS) according to IEEE 802.11, a wireless station and another wireless device termed an access point may communicate with each other.
The wireless station may only periodically (or sporadically) be “fully awake” to receive communication (e.g., beacons) from the AP, being in a low-power/power-down mode otherwise. Typically, the radio portion (containing receive and transmit signal processing chains) is set to the low-power mode, since the radio portion is usually the highest power-consuming portion of a wireless station. Additionally, at least some portions of the rest of the wireless station (e.g., some portions of a processor and some peripherals in the wireless station) may also be set to a low-power mode.
Each of the AP and the wireless station maintains time using corresponding clock circuitry. However, the clocks of the AP and the wireless station may not be perfectly synchronized or aligned with respect to each other, and in general may not keep perfect synchronized time. Due to such clock errors (deviations from synchronization), the power-up instants of the radio portion (and/or any other portion set to low-power mode) of the wireless station may not coincide perfectly with a desired (ideal) wake-up time instant. Instead, the wireless device may wake-up either too early or too late with respect to start of transmission instants of communication (e.g., beacons) from the AP. In either scenario, undesired power consumption occurs in the wireless station.
Several embodiments of the present disclosure are directed to correction of clock errors in a wireless station, and thereby to enable reduction of power consumption in the wireless station.
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